Capital Loss Carryforwards, Valuation Allowance

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- Definition

Income Taxes [Line Items]

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- Definition

Operating Loss Carryforwards And Tax Credit Carryforwards, Valuation Allowance

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- Definition

Operating Loss Carryforwards, Expiration Period

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- Definition

Operating Loss Carryforwards, Tax Effected Amount

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- Definition

Tax Credit Carryforward, Expiration Period

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are not subject to expiration dates.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-6

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-3

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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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- Definition

Amount of unrecognized tax benefits.

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-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
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INCOME TAXES - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
INCOME TAXES - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Taxes [Line Items]
Capital loss carryforwards, valuation allowance	$ 179
Unrecognized tax benefits	70	$ 66	$ 58
Federal \| United Airlines, Inc.
Income Taxes [Line Items]
NOL carryforwards	9,700
Tax effected amount of NOLs	2,000
NOLs without an expiration date	9,600
Federal \| United Airlines, Inc. \| 2029
Income Taxes [Line Items]
NOL carryforwards	100
State
Income Taxes [Line Items]
Tax credits	58
NOL and tax credit carryforwards, valuation allowance	$ 29
State \| Minimum
Income Taxes [Line Items]
Tax credit expiration period	1 year
State \| Maximum
Income Taxes [Line Items]
Tax credit expiration period	15 years
State \| United Airlines, Inc.
Income Taxes [Line Items]
NOL carryforwards	$ 3,000
Tax effected amount of NOLs	$ 200
State \| United Airlines, Inc. \| Minimum
Income Taxes [Line Items]
NOL expiration period	1 year
State \| United Airlines, Inc. \| Maximum
Income Taxes [Line Items]
NOL expiration period	20 years